It was, in the eyes of much of the world, the defining symbol of the George Bush presidency: the prison camp at Guantánamo that deviated from America's founding ideals in its use of torture and indefinite detention.

But the offshore centre that had resonated so strongly in Bush's presidency could be near its end. Barack Obama, in one of his first acts as president, yesterday circulated a draft of an executive order to shut down the camp.

Obama is expected to issue the order today along with additional presidential directives banning waterboarding and other forms of torture.

"The detention facilities at Guantánamo for individuals covered by this order shall be closed as soon as practicable, and no later than one year from the date of this order," the draft said, according to Associated Press which first reported the story.

The draft order also calls for an end to the widely condemned military trials at Guantánamo. Two trials were stopped yesterday as Obama took his first step towards dismantling the justice regime put in place by Bush to try al-Qaida suspects.

Military judges ordered a 120-day suspension of the trial of the former teenage soldier Omar Khadr, which was due to start on 26 January. They also suspended pre-trial hearings for Khalid Sheikh Mohammed and four others accused in the 2001 attacks in the US.

Obama had directed prosecutors to seek a suspension in the Khadr and 9/11 cases within hours of his inauguration on Tuesday to enable a full-scale review of the military commissions system.

"In order to permit the newly inaugurated president and his administration time to review the military commission process generally, and the cases currently pending before the military commissions specifically, the secretary of defence has, by order of the president, directed the chief prosecutor to seek continuances of 120 days in all pending case," the prosecutor, Clay Trivett, said in the written request to the judges.

Human rights groups viewed the order as the beginning of the end for military tribunals and the regime of indefinite detention at Guantánamo.

"This is a giant step forwards towards finally closing Guantánamo," said Anthony D Romero, the executive director of the American Civil Liberties Union. "The 120 days is a time-out that gives the Obama administration time to develop a plan for executing the president's promise to close Guantánamo."

But Vincent Warren, director of the Centre for Constitutional Rights, which has represented hundreds of detainees, said Obama should have provided details of the closure and made a commitment to try terror suspects in US courts. "It only took days to put these men in Guantánamo. It shouldn't take a year to get them out. We are disappointed that he outlined no concrete steps for closing the base and gave his administration an entire year to sort out its plans."

Joanne Mariner, an attorney for Human Rights Watch, who was in the courtroom at Guantánamo yesterday, said it was clear from the prosecution that Obama intended to scrap the entire legal apparatus at the camp, and try the terror suspects in US courts. "They emphasised that this was not a technical thing or a little breather. They emphasised that it was going to be a comprehensive review," she said. "The implication was that this would be ending."

She said there was little visible reaction from the 9/11 suspects to the order, or to Obama's election.

Obama had to move swiftly to shut down the trials to avoid being seen to legitimise the military tribunals put in place by Bush.

Human rights organisations were especially concerned about the 9/11 proceedings. Had Mohammed and the others entered guilty pleas in the tainted tribunals, that might have prevented their prosecution in a US federal court.

Obama has acknowledged that the larger business of shutting down the camp will be more complicated.

Only 18 of the 245 suspects remaining at Guantánamo have been charged. The Obama administration hopes to try these people in US courts and wants to move ahead swiftly in the case against the 9/11 plane hijackers.

There are signs of opposition to transferring the hijackers to US prisons to await trial. Officials in Kansas say they do not want the prisoners at Fort Leavenworth military prison, which is in the state.

But the far greater challenge will be deciding the fate of the majority of detainees who will not be brought to trial. Most have been waiting seven years to be sent home, either as free men or to be transferred to another facility.

Obama intends to conduct a review of the evidence against the detainees to decide which cases should go to trial. He is also hoping that goodwill towards the new administration will encourage other governments to take some of the detainees who cannot return to their home countries.

Switzerland yesterday issued a statement saying it would consider taking some detainees. Portugal has also called on EU states to take in detainees.

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